A 49-year-old Caucasian man sought care for erythematous patches on the dorsal surface of his hands that he’d had for 2 to 3 years. These patches had become increasingly painful when exposed to sunlight. In the past he’d suffered from multiple sunburns. Examination revealed erythematous patches, blisters, and calluses on his hands, and ulcerations and scarred and linear plaques on the bilateral proximal and distal interphalangeal joints. He had no other lesions on his body.
What’s your diagnosis?
This patient had erythropoietic protoporphyria (EPP), a metabolic disease caused by a deficiency in ferrochelatase enzyme activity. Approximately 25% of patients develop hepatobiliary disease, which may be the only manifestation of the disease. EPP most commonly occurs in children ages 2 through 5, but diagnosis can be delayed until adulthood if a patient’s symptoms are mild or do not affect the skin.
Photosensitivity with a stinging or burning sensation on sun-exposed areas distinguishes EPP from other porphyrias. With repeated sun exposure, the affected areas can develop a waxy thickening with shallow linear or elliptical scars that make the skin look older. Blisters, erosions, and crusting can manifest with prolonged sun exposure.
EPP lesions could resemble contact dermatitis, porphyria cutanea tarda, dyshidrotic eczema, solar urticarial, or hydroa vacciniforme. Suspicion of EPP should be high when a patient presents with photosensitivity. Patients with EPP will have an elevated erythrocyte protoporphyrin level and elevated levels of protoporphyrins in feces. Liver enzymes should be ordered to evaluate for hepatobiliary disease.
Our patient began taking beta-carotene supplements to reduce photosensitivity, and tacrolimus 0.1% ointment to treat the lesions on his hands. He also used over-the-counter zinc oxide sun block and skin moisturizer, and reduced his exposure to the sun for several months. The patient saw improvement in his disease, with no further blistering or ulcerations.
Adapted from: Kasper DA, Centilli M, Silverton K. Photo Rounds: erythematous patches on the hands. J Fam Pract. 2012;61:101-104.